NOTE: ANSI C37.06 lists standard ratings. A
short-circuit study is required to specify ratings.
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Oil circuit breakers shall comply with IEEE C37.04 and NEMA SG 4and shall
be of the outdoor three-pole type, with single or multiple tanks and
frame-mounted or floor-mounted on a common base in accordance with the
manufacturer's standard design. Control voltage shall be [48] [125] volts
dc. Ratings shall be as follows:
Nominal voltage...............................[_____]
Rated maximum voltage.........................[_____]
Maximum symmetrical interrupting capacity.....[_____]
Maximum asymmetrical interrupting capacity....[_____]
3-second short time current carrying capacity.[_____]
Close and latch capacity......................[_____]
Rated continuous current......................[_____]
Maximum interrupting time.....................[_____]
Permissible tripping delay....................[_____]
Reclosing time (adjustment range).............[_____]
Duty cycle at rated conditions................[_____]
Basic Insulation Level (BIL)..................[_____]
2.11.1
Incoming Line Circuit Breakers for Substations
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NOTE: Delete items "e" and "f" if not required.
**************************************************************************
Incoming line circuit breakers shall be coordinated with the requirements
of the serving utility, and of the protected transformer, and shall include
the following control and monitoring system items that shall be mounted in
the instrument and relay cabinet.
a.
An ammeter and an ammeter switch.
b.
A circuit breaker control switch for local and remote control
operation.
c.
Three overcurrent relays, devices 50/51.
d.
One residually-connected ground-overcurrent relay, device 50/51N.
e.
Three directional overcurrent relays, device 67.
f.
One ground-directional-overcurrent relay, device 67N.
g.
Three transformer differential relays, device 87T and an auxiliary
SECTION 16475A
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